docs: def gaussian_filter(self, sigma=2, order=0):
          """
          Spatially smooth images with a gaussian filter.
  
          Filtering will be applied to every image in the collection.
  
          Parameters
          ----------
          sigma : scalar or sequence of scalars, default = 2
              Size of the filter size as standard deviation in pixels.
              A sequence is interpreted as the standard deviation for each axis.
              A single scalar is applied equally to all axes.
  
          order : choice of 0 / 1 / 2 / 3 or sequence from same set, optional, default = 0
              Order of the gaussian kernel, 0 is a gaussian,
              higher numbers correspond to derivatives of a gaussian.
          """
          from scipy.ndimage.filters import gaussian_filter
  
          return self.map(lambda v: gaussian_filter(v, sigma, order), value_shape=self.value_shape)